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<object class="largeFonts">
SG User's Guide
</object>

<br />
<br />
Version 0.1
<br />
<br />

<b>Table of Contents</b>
<ol>
<li> <a href="#overview">Overview</a></li>
<li> <a href="#resources">Information and Resources</a></li>
<li> <a href="#download">Obtaining SG</a></li>
<li> <a href="#faq">Frequently Asked Questions</a></li>
<li> <a href="#install">Installation Instructions</a></li>
<li> <a href="#author">Author Information</a></li>
<li> <a href="#license">Copyright and Terms of Use</a></li>
<li> <a href="#gpl">GNU GPL</a></li>
</ol>

<i>
NOTE:
</i>
This documentation provides information about installation, configuration,
and general usage of the SG libraries. 
Information about the programming interface provided by the SG software
can be found in the <a href="api/html/index.html" target="_blank">Programmer's Guide</a>.

<br />
<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="overview">Overview</a></b>

<br />
<br />
SG is an unstructured simplex mesh
OpenGL display and manipulation tool for use with
the finite element research codes <a href="../mc/index.html">MC</a>
and <a href="http://ccom.ucsd.edu/~reb">PLTMG</a>.
SG provides OpenGL-based graphics over UNIX and INET
sockets on UNIX/X-based systems, Win32-based systems, and other systems.
It can also be used with
<a href="../mclite/index.html">MCLite</a>
as a replacement for MATLAB's builtin graphics for polygons.
SG can read Geomview OFF files and OpenInventor files for polygonal
surface descriptions, and it can also read PDB files for molecule descriptions.
SG looks and acts somewhat like Geomview, and it mimics most of the basic
features and controls of Geomview for displaying polygonal 2-manifolds.

<br />
<br />
<a href="images/ucsd2.gif" style="text-decoration: none"><img src="images/120x120/ucsd2.gif" alt="Figure" border="0" align="right" /></a>
SG is designed to mimic the well-known Geomview program from the University
of Minnesota's geometry center, and it uses one of Geomview's input file
formats (the "OFF" format).  Although SG it is quite a bit simpler than
Geomview, it has three advantages when compared to Geomview.  First, it can
take input directly from files, UNIX pipes, UNIX domain sockets, and
INET sockets (Geomview cannot take input from INET sockets).
Second, it can produce provably
correct PostScript renderings of meshes (Geomview uses a baricenter-based
front-to-back ordering for the Painter's algorithm, which often fails for
complex meshes; SG uses a linear programming approach which is
mathematically guaranteed to work if the picture is paintable with the
Painter's algorithm).  Third, it will build and run on Win32 platforms
such as Windows 2000, Windows NT, and Windows 98.
(Some may actually view this as a disadvantage.)
In the case of Win32, SG uses the WINSOCK API for INET socket access.
The window-system specific connection to X11 or Win32 is made through
"WGL" extensions to Win32 under NT, or using the SGI "GLw" widget set 
on X11 platforms.
The graphics in SG is done in an entirely platform-independent manner 
using OpenGL.
This portability is due to SG having been built on top of
a portable low-level abstraction library called MALOC (Minimal Abstraction
Layer for Object-oriented C).  MALOC was written primarily to support the
development of MC, but is now also used for SG.  Both MALOC and SG are now
both used by Randy Bank in the development of his software package PLTMG.

<br />
<br />
<b>
Quaternion-based Trackball Rotator
</b>

<br />
<br />
<a href="images/tr.gif" style="text-decoration: none"><img src="images/120x120/tr.gif" alt="Figure" border="0" align="right" /></a>
SG is a polygonal manifold display and manipulation tool.
It can also display PDB (Protein DataBase) data as a collection of
intersecting triangulated spheres of appropriate color and radii.
It is basically a trackball rotator, although one can also scale and
translate the object being displayed.
The manipulation is done with a combination of the mouse and the keyboard.
The rotator is quaternion-based, following the trackball example in Mark
Kilgard's OpenGL programming book.
The rotator avoids gimbal lock, rotation instability, and other degeneracies
through the use of a projection ball and quaternions.
The hysteresis problem usually present in rotators is removed by employing
Ken Shoemake's non-accumulation trick from his famous Arcball example in
one of the Graphics Gems.
(I.e., when you move the mouse back to the starting point in a rotation,
the object resumes its original position.)

<br />
<br />
<b>
OpenGL-to-Postscript Generation
</b>

<br />
<br />
<a href="images/torus.gif" style="text-decoration: none"><img src="images/120x120/torus.gif" alt="Figure" border="0" align="right" /></a>
SG can generate a very high-quality Postscript rendering of any displayed
scene, with (provably) correct logical rendering order of the polygon
primitives, through the use of builtin routine called SGps.
SGps generates Postscript output from an arbitrary
OpenGL scene, by using the feedback buffer mechanism in OpenGL.
SGps is similar to Seth Teller's PSGL, and to Gary Wu's PSOGL,
but it does not use the same baricentric depth quicksorting of the polygons,
which is prone to incorrect rendering orders for complex scenes.
Instead, SGps is based on a linear programming approach
developed jointly with R. Bank.
If a scene can be rendered by the Painter's Algorithm, then SGps is
guaranteed to find a logically correct painting order, and it will then use
the Painter's Algorithm to render the scene correctly in Postscript.

<br />
<br />
<b>
Input Format
</b>

<br />
<br />
Here are some examples illustrating the Geomview-compatible OFF input format tha
t
SG employs:
<a href="mctri.off">tri</a>,
<a href="mctet.off">tet</a>.
The portability of SG is attained by the use of a low-level
abstraction library called <a href="../maloc/index.html">MALOC</a>.
The MALOC library must be installed before installing SG.
Similar to MALOC, SG is easily buildable from source on any UNIX-like system,
and uses a GNU autoconf build environment.

<br />
<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="resources">Information and Resources</a></b>

<br />
<br />
Detailed information about SG can be found in the
<a href="index.html">User's Guide</a>
and
<a href="api/html/index.html">Programmers's Guide</a>.

<br />
<br />
While SG is itself a self-contained software package, it is one of several
components of 
FETK
(the Finite Element ToolKit).  
FETK
consists of the
following components written in Clean OO C:
<ul>
<li> MALOC - Minimal Abstraction Layer for Object-oriented C programs.</li>
<li> PUNC  - Portable Understructure for Numerical Computing.</li>
<li> GAMer - Geometry-preserving Adaptive MeshER (uses MALOC).</li>
<li> SG    - Socket Graphics mesh display tool (uses MALOC).</li>
<li> MC    - Manifold Code finite element package (uses MALOC and PUNC).</li>
<li> MCX   - MC eXtension libraries (uses MALOC, PUNC, and MC). </li>
</ul>

<br />
MALOC is self-contained, and requires only an ANSI-C compiler on a UNIX
or Win32 platform.  PUNC, GAMer, SG, and MC are also self-contained, but rely 
on MALOC having been previously installed on the platform.  Additional features
of MC are enabled if PUNC is available, but PUNC is not required to build MC.
The MC eXtension libraries MCX are constructed on top of MALOC and MC, and 
in order install and use MCX one must first correctly configure and install 
both MALOC and MC.  MCX is made up of a number of individual libraries 
developed by members of our group, or contributed by one of a number of 
colleagues.  More information about 
FETK
can be found on the 
FETK
website:
<ul>
<li> <a href="http://www.fetk.org/">http://www.fetk.org/</a></li>
</ul>

<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="download">Obtaining SG</a></b>

<br />
<br />
SG is copyrighted, but is redistributable in source and binary form
under the following <a href="#license">license</a>.
The SG source can be downloaded from the 
<a href="http://www.fetk.org/codes/download/index.html">FETK Download Page</a>.
<br />
<br />

In case you are having trouble with X11 on your MacOSX Leopard machine,
here are some precompiled binaries:
<ul>
<li> <a href="http://www.fetk.org/codes/sg/sg-i386-apple" onclick="javascript: pageTracker._trackPageview('/downloads/sg-i386-apple'); ">
     http://www.fetk.org/codes/sg/sg-i386-apple
     </a></li>
<li> <a href="http://www.fetk.org/codes/sg/mcsg-i386-apple" onclick="javascript: pageTracker._trackPageview('/downloads/mcsg-i386-apple'); ">
     http://www.fetk.org/codes/sg/mcsg-i386-apple
     </a></li>
<li> <a href="http://www.fetk.org/codes/sg/bridge-i386-apple" onclick="javascript: pageTracker._trackPageview('/downloads/bridge-i386-apple'); ">
     http://www.fetk.org/codes/sg/bridge-i386-apple
     </a></li>
</ul>

Some older pre-compiled SG and related binaries
for Win32 platforms can be found below:
<ul>
<li> <a href="http://www.fetk.org/codes/sg/mcsg.exe" onclick="javascript: pageTracker._trackPageview('/downloads/mcsg.exe'); ">
     http://www.fetk.org/codes/sg/mcsg.exe
     </a></li>
<li> <a href="http://www.fetk.org/codes/sg/bridge.exe" onclick="javascript: pageTracker._trackPageview('/downloads/bridge.exe'); ">
     http://www.fetk.org/codes/sg/bridge.exe
     </a></li>
</ul>

SG uses the low-level FETK abstraction library
<a href="../maloc/index.html">MALOC</a>,
which must be installed before installing SG.

<br />
<br />
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<hr />
<br />

<b><a name="faq">Frequently Asked Questions</a></b>

<br />
<br />
<b>
What is SG and what does SG stand for?
</b>

<br />
<br />
See the <a href="#overview">Overview</a>.

<br />
<br />
<b>
How to I obtain a copy of the SG source code?
</b>

<br />
<br />
See the <a href="#download">Obtaining SG</a> section.

<br />
<br />
<b>
I managed to get a copy of "sg-VERSION.[i386|src|tar].[rpm|gz]";
how do I now install SG?
</b>

<br />
<br />
See the <a href="#install">Installation Instructions</a>.

<br />
<br />
<b>
You gave me a "patch.gz" file to fix a bug in SG; how do I apply the patch?
</b>

<br />
<br />
To apply patches to upgrade SG to a new version, you first obtain the patch
from me or my webpage as a single file with a name like "patch.gz".  You
apply the patch after you have unpacked the sg.tgz file as described above.
To apply the patch, cd into the directory containing the root SG directory
(called "sg" after unpacking sg.tgz) and execute the "patch" program as
follows (the patch program exists on most UNIX machines):
<ul>
<li>gzip -cd patch.gz | patch -p0</li>
</ul>

<br />
Patch files are simply the output from a recursive "diff" that are used to
represent all differences between two directory trees.  For example, to create
a patch representing the changes from version 1.0 of SG (in directory
sg_1.0 for example) to version 1.1 of SG (e.g. in directory sg_1.1),
I would normally type the following:
<ul>
<li> diff -r -u -N sg_1.0 sg_1.1 > patch1</li>
<li> gzip -v patch1</li>
</ul>
which would produce the gzipped patch file "patch1.gz".  If you had previously
installed version 1.0 of SG but would like to upgrade to version 1.1 of
SG, you could just download the file "patch1.gz" and apply the changes
using the program "patch" as above, rather than downloading and reinstalling
the entire version 1.1 of SG.

<br />
<br />
<b>
I really don't know what I'm doing; how to I get more documentation for SG?
</b>

<br />
<br />
The 
<a href="index.html">User's Guide</a>
and the
<a href="api/html/index.html">Programmers's Guide</a>
contain all of the SG documentation.

<br />
<br />
<b>
Why did you develop SG?  There are many other mesh viewer packages, right?
</b>

<br />
<br />
Yes, there are.  Geomview is awesome.  However, we often want to display the
mesh in a calculation on a local workstation, while running the calculation
on a larger remote (possibly parallel) machine.  For large complex meshes,
opening up a remote X display is extremely slow (the X libraries may not
even exist on the large number crucher).  By running SG on the local
machine, our numerical codes on the remote machine can send polygons in
binary XDR format directly to an INET socket on the local machine.  This is
extremely fast, even for very large datasets.
Finally, we often need to run visualization tools natively on Win32 platforms.

<br />
<br />
There are a couple of things we didn't like about Geomview, which we made
different in SG.  For example, the rotator in Geomview exhibits hysteresis
in the sense that if you return the mouse to its original location when
rotating, the object doesn't actually return to its original position.
SG on the other hand uses a quaternion-based trackball rotator, and uses a
rotation non-accumulation trick due to Ken Shoemake to avoid this type of
hysteresis (the particular trick can be found in one of the Graphics Gems
volumes).  The PostScript generation mentioned above was another reason for
writing SG.

<br />
<br />
<b>
What is in all of these subdirectories?  Where exactly is "SG"?
</b>

<br />
<br />
SG consists of several (class) libraries from which you will call routines
to handle your application.  You will need to write a main driver program
(and any supporting routines you need) and then link to the libraries.
Alternatively, you can build the SG tools "sg" and "mcsg" by doing a
"./configure ; make ; make install" in the tools subdirectory.  These two
tools process and display polygon data, and have functionality and behavior
similar to Geomview.  If you are simply after these two tools, then you
don't need to actually use the libraries and headers that get installed
when you configure/make/make install the SG libraries.  However, the in
order to successfully configure/make/make install the tools sg and mcsg,
you must first succesfully configure/make/make install the SG libraries.

<br />
<br />
As described in the file "INSTALL", you will build all of the libraries in one
shot for your particular architecture, along with various test programs to
verify that the various pieces are functioning correctly.  The libraries end
up in "sg/lib", and the header files are in subdirectories in "sg/inc".

<br />
<br />
The following directory tree is created when you unpack the SG "sg.tgz"
distribution file by following the instructions in the INSTALL document:
<pre style="font-family: Courier New">
                                    sg
                                     | 
                         ------------------------
                        /      |    |       |    \
                       config doc examples src tools
</pre>
<br />
The src directory has the additional subdirectory structure:
<pre style="font-family: Courier New">
                                    src  
                                     |
                      ------------------------------
                     /    |      |    |  |   |   |  \
                aaa_inc aaa_lib base gl glu glw ogl vgl
</pre>
<br />
Within each library source directory is an additional subdirectory,
"sg".  The "sg" subdirectory contains public headers for the library, 
representing the library API; these headers will be installed in the
specified header install directory during the install procedure after
building SG.  (The OpenGL library subdirectories gl, glu, and glw contain
additional OpenGL-specific API files in additional subdirectories.)

<br />
<br />
The following is a brief description of each subdirectory of the package.
<br />
<pre style="font-family: Courier New">
    sg             - The entire SG package
    sg/config      - GNU Autoconf scripts and non-unix config files
    sg/doc         - SG documentation
    sg/examples    - Complex examples and data files for using SG
    sg/src         - SG source code (all source and headers)
    sg/src/aaa_inc - Header installation tools
    sg/src/aaa_lib - Library installation tools
    sg/src/*/sg    - The SG headers (API)
    sg/src/base    - Source for M. Holst's BASE  (SG foundation headers)
    sg/src/ogl     - Source for M. Holst's OGL   (OpenGL rotator kernel)
    sg/src/vgl     - Source for M. Holst's VGL   (Virtual openGL)
    sg/src/gl      - Source files for dubset of B. Paul's MesaGL
    sg/src/glu     - Source files for dubset of B. Paul's MesaGLU
    sg/src/glw     - Source files for dubset of B. Paul's MesaGLw
    sg/tools       - Some binary tools for use with SG
</pre>

<br />
<br />
<b>
Okay, I seem to have installed SG correctly; how do I actually use it now?
</b>

<br />
<br />
Using the SG code is very simple; just type "./mcsg" without arguments and
you get a list of all of the options.  The socket bridging tool functions
similarly; typing "./mcbridge" without arguments gives you a list of all
of the possible options.  The remaining tool "sg" is a motif version of
"mcsg" with similar functionality, but with a more sophisticated button
layout.

<br />
<br />
<b>
What is the class hierarchy?  How are the various libraries related?
</b>

<br />
<br />
Detailed information on the class relationships can be found
in the
<a href="api/html/index.html">Programmers's Guide</a>.
The following directed graph shows the class library dependencies.
(This tends to evolve as MC is developed.)
<br />
<pre style="font-family: Courier New">
   MALOC ==> base ==> ogl ==> vgl ==> sg
                      /\      /\
                      ||      ||
   OpenGL ===> gl => glu      ||
                              ||
   Window System =========> wgl/glw
</pre>

<br />
<br />
<b>
<a name="cooc">
Wait!  I have a bunch of other questions, such as:
</a>
</b>

<ul>
<li>What in tarnation is "Clean OO C"?</li>
<li>Why is SG written in Clean OO C rather than C++ or Objective-C?</li>
<li>Why is SG written on top of this other package with a weird name (MALOC)?</li>
<li>I want to extend SG and/or MALOC in some way; what is the "Coding Style"?</li>
<li>I wrote a cool extension; how do I get it included in SG and/or MALOC?</li>
</ul>
These and other related questions are addressed in the MALOC FAQ, which is
distributed as the README file in the MALOC source distribution.

<br />
<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="install">Installation Instructions</a></b>

<br />
<br />
<b>
Available distribution formats
</b>

<br />
<br />
SG is distributed in both binary format (as a binary RPM file
sg-VERSION.i386.rpm for i386-based versions of Linux) and in source
format (as a source RPM file sg-VERSION.src.rpm and as a gzipped tar
file "sg-VERSION.tar.gz").

<br />
<br />
<b>
Installation using the binary RPM file
</b>

<br />
<br />
The following rpm command will install all of the SG headers and libraries
into /usr/local/include and /usr/local/lib, and will install the SG
documentation into /usr/share/doc/packages/sg:
<pre style="font-family: Courier New">
    rpm -Uvh sg-VERSION.i386.rpm
</pre>

<br />
<b>
Installation and rebuilding from sources using the source RPM file
</b>

<br />
<br />
The following rpm command will unpack the source rpm file
"sg-VERSON.src.rpm" into the SG gzipped tar file containing
the sources called "sg-VERSION.tar.tar.gz" and into a small RPM
spec file called "sg-VERSON.spec":
<pre style="font-family: Courier New">
    rpm -Uvh sg-VERSION.src.rpm
</pre>
The sources can then be unpacked and built using the directions for
the gzipped tar file below.
Alternatively, the following rpm command will do these steps for you:
<pre style="font-family: Courier New">
    rpm -bp sg-VERSION.spec
</pre>

<br />
<b>
Rebuilding binary and source RPM files from the gzipped tar file
</b>

<br />
<br />
The SG sources contain the RPM spec file "sg-VERSON.spec" in the
root source directory; as a result, rebuilding the RPM files from sources
can be done using the rpm command:
<pre style="font-family: Courier New">
    rpm -ta sg-VERSION.tar.gz
</pre>
The result will be the corresponding source and binary rpm files,
named "sg-VERSON.src.rpm" and "sg-VERSION.i386.rpm".
Normally, these files are written to /usr/src/redhat/SRPMS
and /usr/src/redhat/RPMS respectively, but you must be logged in
as root for these to work.
The destination directories can be overriden using arguments to the
rpm program (see the rpm manpage).

<br />
<br />
<b>
Installation and building from sources using the gzipped tar file
</b>

<br />
<br />
The following command will unpack 
SG into a number of subdirectories and files on any UNIX machine 
(and on any WinNT machine with the GNU-Win32 tools gzip and tar).
<pre style="font-family: Courier New">
    gzip -dc sg.tgz | tar xvf -
</pre>

<br />
<b>
Building the package using the GNU "configure" shell script and "make"
</b>

<br />
<br />
The "configure" shell script in the "sg" directory (the toplevel
directory created when you unpacked the SG tgz file) will build the entire
package.  This is a standard GNU autoconf-generated configuration script.
For a list of the possible configuration options, type:
<pre style="font-family: Courier New">
    ./configure --help
</pre>
<br />
You should be able to build SG by simply typing:
<pre style="font-family: Courier New">
    ./configure
    make
    make install
</pre>
<br />
However, it is often advantageous to keep the original source directory
pristine; the configure script can actually be run outside the source
tree, which will keep all files created by the build outside the source
tree.  (This idea is related to the section below describing how to build
binaries for multiple architectures at the same time using the same source
tree, and requires that your version of make has the VPATH facility, such
as GNU make.)  For example, I build SG in a separate directory from the
source tree as follows:
<pre style="font-family: Courier New">
    gzip -dc sg.tgz | tar xvf -
    mkdir sg_build
    cd sg_build
    ../sg/configure
    make
    make install
</pre>

<br />
<br />
<b>
Building binaries for multiple architectures in the same source directory
</b>

<br />
<br />
If you have a version of "make" that supports the VPATH facility (such as
any recent version of GNU make), then you can build the package for multiple
architectures in the same source directory (in fact, you can do the compiles
at the same time without collisions).  This is very useful if you have your
home directory on an NFS volume that you share among multiple architectures,
such as SGI, Linux, etc.  To build SG for all the systems at the same time,
you simply make an additional subdirectory in the main SG directory for
each architecture, copy "configure" into it, "cd" into the subdirectory, and
then install as above.  For example, on a linux machine you would do the
following:
<pre style="font-family: Courier New">
    mkdir linux
    cp configure linux/.
    cd linux
    ./configure
    make
    make install
</pre>
<br />
If you mount the same NFS home directory on for example an OpenStep box,
you could at the same time do the following:
<pre style="font-family: Courier New">
    mkdir next
    cp configure next/.
    cd next
    ./configure
    make
    make install
</pre>
<br />
Again, both builds can actually be done outside the source tree rather
than in a subdirectory of the source tree, as described in the previous
section.

<br />
<br />
<b>
Building shared libraries rather than static libraries
</b>

<br />
<br />
(MIKE: give an overview of libtool.)

<br />
<br />
<b>
Rebuilding the configure script and the Makefile.in files
</b>

<br />
<br />
If for some reason you actually need to rebuild the configure script or the
Makefile.in files using the GNU autoconf suite, you should read the block of
documentation at the top of the configure.in file.  The commentary I put there
explains exactly how the GNU autoconf suite must be used and in what order,
and exactly what files are produced at each step of the process.  A script
called "bootstrap" which automates this process is located in the config
subdirectory of the SG source tree.

<br />
<br />
<b>
Platform-specific information
</b>

<br />
<br />
Below is some platform-specific build/usage information for SG.
<ul>
<li>Linux   (Source:  M. Holst, UCSD)
<br />
<br />
    Things should work as described above.
<br />
<br />
</li>
<li>FreeBSD/NetBSD/OpenBSD   (Source:  M. Holst, UCSD)
<br />
<br />
    Things should work as described above.
<br />
<br />
</li>
<li>OpenStep   (Source:  M. Holst, UCSD)
<br />
<br />
    Things should just work, but you may have to set the CC environment
    variable as follows before typing ./configure:
<pre style="font-family: Courier New">
    export CC="/bin/cc"
</pre>
    or you might need to use:
<pre style="font-family: Courier New">
    export CC="/bin/cc -ObjC"
</pre>
<br />
</li>
<li>IRIX   (Source:  M. Holst, UCSD)
<br />
<br />
    If you are on a 64-bit IRIX box such as an Onyx, Octane, or Origin,
    set the CC environment variable as follows before typing ./configure: 
<pre style="font-family: Courier New">
    export CC="/bin/cc -64"
</pre>
    If you are on a 32-bit IRIX box such as an O2 or Indy,
    set the CC environment variable as follows before typing ./configure: 
<pre style="font-family: Courier New">
    export CC="/bin/cc -32"
</pre>
<br />

</li>
<li>Win32   (Source:  M. Holst, UCSD)
<br />
<br />
    Unless you have the Cygwin environment, you need to use one of the
    included project file collections for one of the commercially
    available ANSI C or C++ compilers for the Win32 environment.
</li>
</ul>

<br />
<b>
What you end up with
</b>

<br />
<br />
Once the build completes via the "configure;make;make install" procedure above
with no errors, the SG library (libsg.a and/or libsg.so) is installed
into the specified installation directory.  You can also build some useful
tools that employ the SG library by cd-ing into the "tools" subdirectory and
repeating the "configure;make;make install" procedure.
Once the tools build completes, you will end up with:
<pre style="font-family: Courier New">
    mcsg     - Core socket OpenGL tool ([GLw | WGL] + [X | Win32] + OpenGL)
    mcbridge - A socket bridging tool (FILE/PIPE/UNIX/INET)
    sg       - A Motif version of mcsg (Motif + X + OpenGL)
</pre>
<br />
If the SG tools work like they were designed, you won't need any more
information to use the tools.  If you want to know more about the details
of the algorithms in SG, or about the implementation details such as the
socket graphics, have a look at the
<a href="api/html/index.html">Programmer's Guide</a>.

<br />
<br />
<b>
Getting SG to find your installation of GL/GLU/GLw/Motif/Etc
</b>

<br />
<br />
If your installation of OpenGL (libGL, libGLU, libGLw and headers) and/or
Motif is located in an unusual directory, then the configuration script may
have trouble finding the libraries or the headers.  The configure script
prints out the state of affairs quite clearly as to whether it found the
libraries and the headers.  If you have the libraries and configure is not
finding them, then here are several possible solutions, each of which usually
works.  They are listed in preferred order (i.e. you should try Solution 1
first, and if that doesn't work try Solution 2, and so on).

<br />
<br />
Note that you DO NOT need Motif in order to build SG; if you DO have Motif,
then the additional Motif-based tool "sg" is built.  Without
Motif libraries on your system, you still get the base socket graphics tool
"mcsg" and the socket bridging tool "mcbridge".  ("sg" is
somewhat fancier than "mcsg", but "mcsg" has all of the core functionality
of the Motif tool.)  On a Win32 machine such as Windows NT, you will also
end up with both "mcsg" and "mcbridge".
<ul>
<li>Solution 1:
<br />
<br />
    Have your system administrator install MPI in a proper system
    directory so that MALOC (and other AUTOCONF-based codes) can find it!
<br />
<br />
</li>
<li>Solution 2:
<ol>
<li>Find the location of the OpenGL libraries and headers and the
    Motif libraries and headers on your system, either by asking your
    sysadmin, poking around yourself, or (if you have it) using the
    "locate" utility:
<pre style="font-family: Courier New">
    locate libGL.a
    locate libGLU.a
    locate libGLw.a
    locate gl.h
    locate glu.h
    locate GLwDrawA.h
    locate libXm.a
    locate Xm.h
</pre>
    On my Redhat6.2 Linux box with LessTif supplying Motif, XiGraphics'
    supplying two of the OpenGL libraries (libGL and libGLU), and Mesa
    supplying the third (libGLw), the following output is produced:
<pre style="font-family: Courier New">
    mc:~% locate libGL.a
    /usr/lib/libGL.a
    mc:~% locate libGLU.a
    /usr/lib/libGLU.a
    mc:~% locate libGLw.a
    /usr/local/lib/libGLw.a

    mc:~% locate gl.h
    /usr/include/GL/gl.h
    mc:~% locate glu.h
    /usr/include/GL/glu.h
    mc:~% locate GLwDrawA.h
    /usr/local/include/GL/GLwDrawA.h

    mc:~% locate libXm.a
    /usr/X11R6/lib/libXm.a
    mc:~% locate Xm.h
    /usr/X11R6/include/Xm/Xm.h
</pre>
    Therefore, my OpenGL libraries are installed as:
<pre style="font-family: Courier New">
    /usr/lib/libGL.a
    /usr/lib/libGLU.a
    /usr/X11R6/lib/libGLw.a
</pre>
    and the associated OpenGL headers are installed as:
<pre style="font-family: Courier New">
    /usr/include/GL/gl.h
    /usr/include/GL/glu.h
    /usr/local/include/GL/GLwDrawA.h
</pre>
    My Motif library is installed as:
<pre style="font-family: Courier New">
    /usr/X11R6/lib/libXm.a
</pre>
    and the associated Motif headers are installed as:
<pre style="font-family: Courier New">
    /usr/X11R6/include/Xm/Xm.h
</pre>
</li>
<li>Before running the configure script, preset the environment
    variables:
<pre style="font-family: Courier New">
    FETK_GL_LIBRARY,    FETK_GL_INCLUDE,
    FETK_GLU_LIBRARY,   FETK_GLU_INCLUDE,
    FETK_GLW_LIBRARY,   FETK_GLW_INCLUDE,
    FETK_MOTIF_LIBRARY, FETK_MOTIF_INCLUDE,
</pre>
    to point to the directories containing:
<pre style="font-family: Courier New">
    libGL.a,  gl.h,
    libGLU.a, glu.h,
    libGLw.a, GLwDrawA.h,
    libXm.a,  Xm.h,
</pre>
    respectively.  Under bash, using the results from the example
    above, I would do this as follows:
<pre style="font-family: Courier New">
    export FETK_GL_LIBRARY=/usr/lib
    export FETK_GL_INCLUDE=/usr/include
    export FETK_GLU_LIBRARY=/usr/lib
    export FETK_GLU_INCLUDE=/usr/include
    export FETK_GLW_LIBRARY=/usr/local/lib
    export FETK_GLW_INCLUDE=/usr/local/include
    export FETK_MOTIF_LIBRARY=/usr/X11R6/lib
    export FETK_MOTIF_INCLUDE=/usr/X11R6/include
    ./configure
</pre>
    The configure script should now report that it successfully
    found the libraries and headers, and then SG should compile
    without error.
</li>
</ol>
</li>
</ul>

<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="author">Author Information</a></b>

<br />
<br />
SG (Socket Graphics) was conceived,
designed, and implemented over several years by 
<a href="http://ccom.ucsd.edu/~mholst/">Michael Holst</a>,
beginning with an initial implementation in 1994.
Various colleagues have contributed ideas and/or code to SG
(see the credits list below).
<pre style="font-family: Courier New">
    SG (Socket Graphics)
    Copyright (C) 1994--

    Michael Holst               TELE:  (858) 534-4899
    Department of Mathematics   FAX:   (858) 534-5273
    UC San Diego, AP&amp;M 5739     EMAIL: mholst@ccom.ucsd.edu
    La Jolla, CA 92093 USA      WEB:   http://ccom.ucsd.edu/~mholst
</pre>
SG was designed to be a portable networked visualization tool for use in the
development of MC (Manifold Code), an adaptive multilevel finite element
package also developed by 
<a href="http://ccom.ucsd.edu/~mholst/">Michael Holst</a>.
It is also used by Randy Bank as
the primary visualization tool for PLTMG.  Both SG and MC are written on top
of a low-level abstraction layer called MALOC (Minimal Abstraction
Layer for Object-oriented C), also developed by 
<a href="http://ccom.ucsd.edu/~mholst/">Michael Holst</a>.
SG was developed almost
entirely on a home-grown 90Mhz Pentium PC running various flavors of
Linux and [Free|Net|Open]BSD, using primarily GNU, BSD, and other free
software development tools.  Most of the development occurred during the
hours of 10pm to 2am on a daily basis for several years, under heavy
influence of Starbuck's coffee, with helpful advice provided by Mac and
Mochi (two cats knowledgable in socket programming and numerical analysis).

<br />
<br />
SG was released under the GNU GPL (GNU General Public License) beginning
with the initial implementation in 1994, and continues to be released under
this license.  What this means is that like all
GNU software, SG is freely redistributable in source code form following
the rules outlined in the text of the GNU GPL.  You should have received a
copy of the GNU GPL with this distribution of SG; a copy can be found
<a href="#gpl">here</a>.
If you did not receive a copy of the GNU GPL, please write to me and also
write to:
The Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

<br />
<br />
<b>
Software included in the SG source code package
</b>

<br />
<br />
A complete roadmap to the source code forming the SG package can be
found above.
While the core SG classes were developed primarily by 
<a href="http://ccom.ucsd.edu/~mholst/">Michael Holst</a>,
some additional software is currently included with SG:
<pre style="font-family: Courier New">
    sg/src/vgl/vglm.c    - Motif Variant of vgl (joint Bank/Holst effort)
    sg/src/vgl/oglps.c   - Perfect PS generation (joint Bank/Holst effort)
    sg/src/gl/*          - B. Paul's MesaGL (the GL library)
    sg/src/glu/*         - B. Paul's MesaGLU (the GLU library)
    sg/src/glw/*         - SGI's OpenGL widgets (the GLw library)
</pre>
The extra conditionally-build libraries provide the complete OpenGL
capability that SG requires in order to function, if these libraries
are not available on the particular platform.  Under normal circumstances,
these three libraries will not have to be built; the OpenGL API they
provide is completely software-based, and will be slower than native
hardware-accelerated OpenGL which is normally available on modern
PCs, Macs, and SGI platforms.

<br />
<br />
<b>
Credits
</b>

<br />
<br />
Below is a credits list for the people that have
contributed to SG in one way or another.
The fields below follow the credits file format used in the
Linux kernel CREDITS file to allow for easy manipulation via shell scripts.
The fields are as follows:
<br />
<pre style="font-family: Courier New">
          N: name of contributor
          E: email address
          W: web address
          P: PGP key ID and fingerprint
          D: description of primary contributions
          S: snail-mail address
</pre>
<br />
<pre style="font-family: Courier New">
N: Michael Holst
E: mholst@ccom.ucsd.edu
W: http://ccom.ucsd.edu/~mholst
P: 1024/0xB5212DCD
D: sg/*                      -- The package structure
D: sg/acconfig.h             -- The platform abstraction information
D: sg/configure.in           -- The GNU autoconf/automake structure
D: sg/config/*               -- The GNU autoconf/automake shell scripts
D: sg/doc/*                  -- The package documentation
D: sg/examples/*             -- The package examples
D: sg/src/aaa_inc/*          -- Library header build structure
D: sg/src/aaa_lib/*          -- Static and shared library build structure
D: sg/src/base/*             -- M. Holst's SG Foundation headers
D: sg/src/ogl/*              -- M. Holst's OpenGL-based trackball rotator
D: sg/src/vgl/*              -- M. Holst's window system abstraction layer
D: sg/src/gl/*               -- The libGL wrapper
D: sg/src/glu/*              -- The libGLU wrapper
D: sg/src/glw/*              -- The libGLw wrapper
D: sg/tools/*                -- Tools built on the libraries
S: Department of Mathematics
S: UC San Diego, AP&amp;M 5739
S: La Jolla, CA 92093 USA

N: Randolph E. Bank
E: reb@sdna1.ucsd.edu
D: sg/src/vgl/vglm.c         -- Vglm Class (Motif variant; joint w/ Holst)
D: sg/src/ogl/oglps.c        -- OglPS Class (Perfect PS; joint w/ Holst)
S: Department of Mathematics
S: UC San Diego
S: La Jolla, CA 92093 USA

N: Steve Bond
E: bond@ccom.ucsd.edu
D: sg/sg.spec                -- RPM support (for building src/binary RPMs)
S: Department of Mathematics
S: UC San Diego
S: La Jolla, CA 92093 USA
</pre>

<br />
<br />
<b>
Contacting the Author
</b>

<br />
<br />
If you have questions or comments about SG, please feel free to contact
me at <a href="mailto:mholst@ccom.ucsd.edu">mholst@ccom.ucsd.edu</a>.

<br />
<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="license">Copyright and Terms of Use</a></b>

<i>Please acknowledge your use of SG and 
FETK
</i> by citing:
<ul>
<li> M. Holst, Adaptive numerical treatment of elliptic systems on manifolds.
     <i>Advances in Computational Mathematics</i>,
     <b>15</b> (2001), pp. 139-191.
</li>
</ul>

<br />
<br />
This version of SG is distributed under the following guidelines:

<ul>
<li>
   SG (Socket Graphics)
<br />
   Copyright (C) 1994-2010  Michael Holst
   
<br />
<br />
   This program is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 2 of the License, or (at your
   option) any later version.
   
<br />
<br />
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   See the GNU General Public License for more details.
   
<br />
<br />
   You should have received a copy of the GNU General Public License along
   with this program; if not, write to the Free Software Foundation, Inc.,
   675 Mass Ave, Cambridge, MA 02139, USA.
</li>
</ul>

<br />
<!-- ===================================================================== -->
<hr />
<br />

<b><a name="gpl">GNU GPL</a></b>

<br />
<br />
The GPL (GNU General Public License) below is copyrighted by the
Free Software Foundation.  However, the instance of software that
it refers to, my package in this case, is copyrighted by myself as
the author of the package.  Any additional software that I distribute
with my software is copyrighted by the authors of those pieces of
software (see the individual source files for author information).
---Michael Holst

<!-- ===================================================================== -->

<pre style="font-family: Courier New">
		    GNU GENERAL PUBLIC LICENSE
		       Version 2, June 1991

 Copyright (C) 1989, 1991 Free Software Foundation, Inc.
 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

			    Preamble

  The licenses for most software are designed to take away your
freedom to share and change it.  By contrast, the GNU General Public
License is intended to guarantee your freedom to share and change free
software--to make sure the software is free for all its users.  This
General Public License applies to most of the Free Software
Foundation's software and to any other program whose authors commit to
using it.  (Some other Free Software Foundation software is covered by
the GNU Library General Public License instead.)  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
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this service if you wish), that you receive source code or can get it
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in new free programs; and that you know you can do these things.

  To protect your rights, we need to make restrictions that forbid
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These restrictions translate to certain responsibilities for you if you
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  For example, if you distribute copies of such a program, whether
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  Finally, any free program is threatened constantly by software
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		    GNU GENERAL PUBLIC LICENSE
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  0. This License applies to any program or other work which contains
a notice placed by the copyright holder saying it may be distributed
under the terms of this General Public License.  The "Program", below,
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is covered only if its contents constitute a work based on the
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  1. You may copy and distribute verbatim copies of the Program's
source code as you receive it, in any medium, provided that you
conspicuously and appropriately publish on each copy an appropriate
copyright notice and disclaimer of warranty; keep intact all the
notices that refer to this License and to the absence of any warranty;
and give any other recipients of the Program a copy of this License
along with the Program.

You may charge a fee for the physical act of transferring a copy, and
you may at your option offer warranty protection in exchange for a fee.

  2. You may modify your copy or copies of the Program or any portion
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    a) You must cause the modified files to carry prominent notices
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    b) You must cause any work that you distribute or publish, that in
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    part thereof, to be licensed as a whole at no charge to all third
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    c) If the modified program normally reads commands interactively
    when run, you must cause it, when started running for such
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These requirements apply to the modified work as a whole.  If
identifiable sections of that work are not derived from the Program,
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this License, whose permissions for other licensees extend to the
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Thus, it is not the intent of this section to claim rights or contest
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In addition, mere aggregation of another work not based on the Program
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  3. You may copy and distribute the Program (or a work based on it,
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			    NO WARRANTY

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		     END OF TERMS AND CONDITIONS

	    How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
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  To do so, attach the following notices to the program.  It is safest
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    (one line to give the program's name and a brief idea of what it does.)
    Copyright (C) 19yy  &lt; name of author >

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


Also add information on how to contact you by electronic and paper mail.

If the program is interactive, make it output a short notice like this
when it starts in an interactive mode:

    Gnomovision version 69, Copyright (C) 19yy name of author
    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, the commands you use may
be called something other than `show w' and `show c'; they could even be
mouse-clicks or menu items--whatever suits your program.

You should also get your employer (if you work as a programmer) or your
school, if any, to sign a "copyright disclaimer" for the program, if
necessary.  Here is a sample; alter the names:

  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
  `Gnomovision' (which makes passes at compilers) written by James Hacker.

  &lt; signature of Ty Coon >, 1 April 1989
  Ty Coon, President of Vice

This General Public License does not permit incorporating your program into
proprietary programs.  If your program is a subroutine library, you may
consider it more useful to permit linking proprietary applications with the
library.  If this is what you want to do, use the GNU Library General
Public License instead of this License.
</pre>

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